What should be the cell temperature control for a 0-pole spacing electrolyzer?
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According to the FAQs on caustic soda production using the ion exchange membrane process, the temperature inside the electrolyzer is generally kept below 90 degrees; it should not exceed this level, as otherwise vaporization may occur. However, some colleagues say that when the zero-electrode distance is used, the temperature must be kept below 86 degrees. Why is that?
The operating current at a high membrane pole distance requires the alkali solution temperature to be controlled at 85°C; this is mainly to ensure the tolerance of the ion membrane inside the cell, as local temperatures within the cell may exceed the technical specifications set by the membrane manufacturers. Similarly, for cells with a membrane spacing, the cell voltage per cell cannot exceed 3.5 V, for the same reasons mentioned above. Please exercise strict control.
The tank temperature should not exceed 87 degrees; specific control measures need to be determined by analyzing the operation of the electrolyzer, with individual cases being addressed on a case-by-case basis. The heat carried away by the zero-pole distance slot is relatively slower, so the control value is set lower.
This post was last edited by tianjiao362 on 2019-2-8 22:39. Regarding the issue of the temperature in electrolyzers, I personally believe that one should not blindly follow what is written in textbooks. The tank temperature should not exceed 90 degrees; in other words, 90 degrees represents the optimal theoretical value. However, it is very difficult to achieve such a constant value; as a result, many manufacturers control the temperature at 86±2 degrees. This temperature is also controlled under high current and high electric density conditions. At the same time, as the flow rate in the cell increases and the gas-liquid ratio rises, the temperature carried away also increases. Conversely, at low currents and with operation at a low electric density, the flow rate decreases and the gas-liquid ratio drops, which slows down the rate at which heat is removed. In such cases, maintaining a high tank temperature can cause damage to both the electrodes and the ion exchange membrane. In other words, a higher temperature is not necessarily suitable for every current range; it is necessary to determine where the manufacturer’s equipment is located, so as to achieve the most efficient and cost-effective operating conditions using the ion membrane available there !